﻿using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

namespace AbpProjectTemplate.Utilities
{
    public static class EncryptHelper
    {
        /// <summary>
        /// 32位MD5加密
        /// </summary>
        public static string Md5(string source)
        {
            StringBuilder sb = new StringBuilder(32);
            var md5 = MD5.Create();
            byte[] t = md5.ComputeHash(Encoding.Default.GetBytes(source));
            for (int i = 0; i < t.Length; i++)
            {
                sb.Append(t[i].ToString("x").PadLeft(2, '0'));
            }
            return sb.ToString();
        }
        /// <summary>
        /// SHA256
        /// </summary>
        public static string Sha256(string data)
        {
            byte[] bytes = Encoding.UTF8.GetBytes(data);
            byte[] hash = SHA256.Create().ComputeHash(bytes);

            StringBuilder builder = new StringBuilder();
            for (int i = 0; i < hash.Length; i++)
            {
                builder.Append(hash[i].ToString("x2"));
            }

            return builder.ToString();
        }
        /// <summary>
        /// DES加密字符串
        /// </summary>
        /// <param name="pToEncrypt">待加密的字符串</param>
        /// <param name="sKey">加密密钥,要求为8位</param>
        /// <returns>加密成功返回加密后的字符串，失败返回源串</returns>
        public static string DesEncrypt(string pToEncrypt, string sKey)
        {
            StringBuilder ret = new StringBuilder();
            try
            {
                var des = DES.Create();
                byte[] inputByteArray = Encoding.Default.GetBytes(pToEncrypt);
                des.Key = Encoding.ASCII.GetBytes(sKey);
                des.IV = Encoding.ASCII.GetBytes(sKey);
                MemoryStream ms = new MemoryStream();
                CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);
                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();
                foreach (byte b in ms.ToArray())
                {
                    ret.AppendFormat("{0:X2}", b);
                }
                return ret.ToString();
            }
            catch
            {
                return pToEncrypt;
            }
        }
        /// <summary>
        /// DES解密字符串
        /// </summary>
        /// <param name="pToDecrypt">待解密的字符串</param>
        /// <param name="sKey">解密密钥,要求为8位,和加密密钥相同</param>
        /// <returns>解密成功返回解密后的字符串，失败返源串</returns>
        public static string DesDecrypt(string pToDecrypt, string sKey)
        {
            MemoryStream ms = new MemoryStream();
            try
            {
                var des = DES.Create();
                byte[] inputByteArray = new byte[pToDecrypt.Length / 2];
                for (int x = 0; x < pToDecrypt.Length / 2; x++)
                {
                    int i = (Convert.ToInt32(pToDecrypt.Substring(x * 2, 2), 16));
                    inputByteArray[x] = (byte)i;
                }
                des.Key = Encoding.ASCII.GetBytes(sKey);
                des.IV = Encoding.ASCII.GetBytes(sKey);
                CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);
                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();
                return System.Text.Encoding.Default.GetString(ms.ToArray());
            }
            catch
            {
                return pToDecrypt;
            }
        }
    }
}
